Prognostic Groups in 1,676 Patients with T3 Rectal Cancer Treated without Preoperative Radiotherapy

Purpose  The use of preoperative radiotherapy in patients with T3 tumors shows considerable variation among countries and institutions. The Norwegian guidelines have been very restrictive, limiting the indication to T4. This study was designed to identify subgroups of patients with T3 tumors with presumed high risks on adverse outcome and to use these results to reevaluate the national guidelines for preoperative radiotherapy.